1. Field of the Invention
This present invention concerns the area of bags that include closure devices operated by a slider.
Many devices of this type have already been proposed.
The bag closure devices generally include two zipper elements of the complementary male/female type or of the complementary hook type, designed to allow multiple successive openings and closures.
The slider has as its objective to facilitate the joining and the separation of the zippers respectively.
2. Description of Related Art
The attached FIGS. 1 to 5 show a slider-type closure device according to existing designs.
As can be seen in-these figures, the slider 100 generally includes a base 110 which carries two lateral walls 120, 130 and a low central ridge 140. The walls 120, 130 and the low ridge 140 combine to form two channels 150, 160 which are not parallel at least in part. These channels receive elements that are connected respectively to two zipper mouldings 200, 250.
The known sliders have already given great service. They facilitate the opening and the closure of the bags, since it suffices to move the slider, and according to the direction of motion of the latter, to separate or join the zippers because of the non-parallel nature of the channels 150, 160.
However the bags thus equipped has a serious drawback, in that the sliders are sometimes observed to pull apart, and in particular there is a risk of ingestion by children.
In an attempt to reduce this risk, people have already proposed, as illustrated in the appended figures, the addition to the free edged of the walls 120, 130 of the longitudinal ribs 122, 132 designed to take up position under the zippers. However this measure proved to be insufficient. In the event of a large force being applied to the slider, the walls 120, 130 are separated and the slider pulled off.
As illustrated in FIGS. 3, 4 and 5, there have also been proposals to place a soleplate 142 on the end of the low central ridge 140. The soleplate 142 is intended to take up position under the zippers 200, 250 as can be seen in FIGS. 4 and 5. However here again, this solution does not give total satisfaction. In fact, the soleplate 142 must have a shape which is tapered in the direction of the convergence of the channels 150, 160 in order not to interfere with the closure of the bag. In practice therefore, one observes that the risk of pulling-off of the slider still remains, in particular by pivoting and extraction by the tapered end of the soleplate which acts in the manner of a wedge forcing the zippers apart.
Document U.S. Pat. No. 5,664,299 proposed another solution, illustrated in FIG. 6 attached, which consists of adding to the outer face of the backing-strips 202, 252 bearing the complementary closure zippers 200, 250, ribs 204, 254 which are designed to press against the longitudinal ribs 122, 132 of the slider. However this solution also fails to give total satisfaction. It turns out in fact that if a pulling force is applied to the slider, ribs 204, and 254 tend to slide on ribs 122 and 132, and this tends to draw the two closure elements together, and to guide them toward the free passage between ribs 122 and 132, contrary to the initial objective of locking and retention.
Another solution was proposed in document FR-A-2855 153. This solution is illustrated in FIG. 7. It consist of providing, on at least one of the closure elements, a structure 210, 260 that is concave toward the interior of the bag, forming an end-stop for the soleplate 242 in order to prevent the withdrawal of the slider 100 under the effect of a pulling force.
BRIEF SUMMARY OF THE INVENTION
This present invention has as its objective to perfect the known devices by limiting the risk of slider pull-off.
This objective is attained in the context of this present invention by virtue of a closure assembly that includes two complementary elements which are suitable to be successively joined and separated, and a slider that includes a base, two lateral walls, a low central ridge and a soleplate connected to the low central ridge, characterised by the fact that at least one of the two elements has, on its inside surface, a structure that is able to press against the soleplate under the effect of a pulling force so that, under the effect of this force, the said element tends to be flattened against the associated lateral wall of the slider.
As will be explained in what follows, in contrast to document U.S. Pat. No. 5,664,299, the structure thus proposed in the context of this present invention leads to a strengthening of the contact, and therefore an increase in the friction, between the lateral walls of the slider and the closure assembly, in the event of applying a pulling force.
This present invention also concerns bags that are equipped with such a closure assembly.